The invention relates to vapor compression systems and, more particularly, to vapor compression systems utilizing an improved configuration of bypass refrigerant circuit and control features so as to provide enhanced system performance at part-load operation, thus improving life-cycle cost of the unit.
Vapor compression systems often use compressors such as scroll compressors, screw compressors, two-stage reciprocating compressors and the like. Such compressors may have an intermediate pressure port for operating in an unloaded mode, for example when capacity reduction is desired to match external load, or in an economized mode, when performance boost is desirable.
Unfortunately, when operating typical compression systems in unloaded modes, efficiency is not as good as is desirable.
Thus, the need remains for vapor compression systems which can be operated in unloaded modes with enhanced efficiency without compromising full-load operation.
It is therefore the primary object of the present invention to provide such a system.
It is a further object of the invention to provide such a system wherein equipment cost is not increased.
Other objects and advantages of the present invention will appear hereinbelow.